Aviation beacon



Aug. 11, 1925. 1,548,958

E. A, SPERRY AVIATION BEACON Filed v May 4, 1921 3 Sheets-Sheet l 'ugf ll, 1925.

3 Sheets-Sheet A2 E A SPERRY l AVIATION BEACON Fi1ed May 4, 19215min/who@ Y EPEHRX Aug. 11, 1925. 1,548,958

E. A. SPERRY AVIATION BEACON Filed May 4, 1921 3 sheets-sheet :s .Zyl 7|Patented Aug. 11, 1925.

UNITED STATES ELMER A. SPERBY, F BROOKLYN, NEW YORK.

AVIATION BEACON.

Application led Hay 4,

j York, has invented certain new and useful Improvements in AviationBeacons, of which the following is a specification.

This invention relates to lightprojecting means and has for its chiefobject the provision of an eficient beacon especially adapted foraviation purposes, such as informing an aviator of his whereabouts orindicating the presence of a landing eld. Another object is to provide abeacon whereby a powerful beam of light may be Vdirected substantiallyvertically and kept in a state of motion. It is found that a beam whichis moving is visible for greater distances than a beam which is at rest,even though the latter be of the same intensity as the moving beam. Ithus increase the visibility of a beam of given intensity by moving it.When the beam is derived from a searchlight of the modern high intensitytype and is ke t continuously moving, an exceptionally e ective aviationbeacon results. A further object is the. provision of simple andreliable means for continuously moving the beam. Other objects andadvantages will become apparent asthe description of the invention ishereinafter developed.

Referring to the drawings wherein I have shown what I now consider to bethe preferred forms of my invention,

Fig. 1 is a vertical sectional view showing one form of my invention.

Fig. 2 is a vertical section showing a modiication.v

Fig. 3 is a view in elevation of a detail.'

Fig. 4 is a sectional view of a third form of my invention. v

Fig. 5 is a vertical sectional View of still another modification.

Fig. 6 is a view taken at right angles to' Fig. 5. .A

Fig. 7 is a view of another form of my invention.

Fig. 8 is a vertical sectional view of another modification.

For projecting a beam I have shown in Fig. l a searchlight mechanismenclosed within a suitable drum 1. The latter may be mounted in theusual manner for turning about a horizontal axis upon the base 2 thelatter being rotatable about a vertica 1921. Serial No. 466,774.

axis on lower |base member 3. For conveniently rotating the searchlightdrum about a vertical axis a motor 64 may be provided; which motordrives a worm wheel 65 attached to the rotatable member 2. Within thedrum are the positive and negative electrodes4 and 5 supported in theusual electrode holders 6 and 7 respectively, which in turn are carriedby standards 8 and 9 supported by the drum. Electrode rotating andfeedin mechanism of any conventional type may be employed, such forexample as shown in my prior Patent No. 1,282,133, granted October 22q1918. A box 10 attached to the drum may serve to enclose eertain partsof said mechanism as is well understood in the art. I prefer to utilizethe modern high intensity arc in order to obtain a beam of maximumbrilliancy. The pro` duction of the high intensity effect requireseither that one electrode be inclined with respect to the other or thatthe arc be deflected. I have shown the electrodes substantially inalignment, and forthe purpose of deflecting the arc a bus bar 11 may besupported adjacent the arc on standards 8 and 9. This bus bar is incircuit with the arc and electrodes. In the arrangement shown in Fig. 1said bus bar is electrically connected to the negative electrode and isinsulated from the standard 8 which conducts current to the positiveelectrode. The

crater of the positive electrode 4 is preferably located at the focalpoint of the light condenser or parabolic reflector 12, which reflectorprojects the beam of light thru the ltransparent front 60 of thesearchlight. I

prefer that the searchlight be turned upon its horizontal axis into theposition shown to direct the beam vertically upward, since a verticalbeam can be seen for long distances.

As I have previously pointed out, the visibility of a beani of light ofgiven intensity can be increased by moving the same. Accordingly I haveprovided means for keeping the beam in a constant state of motion. Bythe means which I haveprovided the beam may be caused to rotate in suchmanner as to describe any of various paths. In Fig. l I have shown oneform of means for attaining this end by moving the reflectorindependently of the electrodes. This means may be constructed andarranged substantially as follows:

Pivotally mounted in any suitable manner within the searchlight drum formovement l about an axis 13 is a ring 14,` from which ring the reflector12 is suspended by arms 15. The latter are pivotal y connected to ring14 by trunnions 15 for movement about an axis at right angles tosaidaxis 13. Preferably the crater of the positlve electrode, whichconstitutes the prmcipal' source .of light, is positioned not only atthe -focal point of reiector 12 but also at the intersection of axis 13and the axis about which mirror 12 is movable with respect to ring 14.In other words the focalopoint of mirror 12 preferably coincides withthe center of the Cardan mounting, and the positive crater should bepositioned at this point. In this manner the said crater will remaincontlnually at the focal point of the mirror or reiiector regardless ofthe turning movements of the latter. For turning the ring 14 and mirror12 about axis 13 I have shown a motor 16 supported by the searchlightdrum and driving through the worm 17 a crank 18 to which iseccentrically connected a link 19. The latter is also connected to anarm 20 depending from ring 14. By this means the ring 14 and refieotor12 may be oscillated continuously about axis 13. Similar mechanism maybe employed for oscillating reflector 12 with respect to ring 14. Thus,a motor 21 may be suspended by a bracket 22 from said ring and may drivea crank 23 connected by an eccentric link 24 with an arm 25 dependingfrom the reflector.

From the above arrangement it will' readily be seen that the searchlightbeam can be oscillated simultaneously about4 axis 13 and the axis oftrunnions 15. The motors 16 and 21 may be electric motors of anyconventional type. The beam can be made to traverse various paths byvarying the relative speeds of rotation of the motors 16 and 21 or byvarying the interval between the arrival of ring 14 at one of its limitsof oscillation and the arrival of the mirror 12 at one of the limits ofits oscillatory movement about the axis of trunnions 15. By properlyadjusting said motors it will be evident that the beam can be caused todescribe a cone the axis of which is the axis of the searchlight.

The positive electrode may be replaced through an aperture 26 in theglass front of the searchlight. The condenser or re-` flector 12 may beprovided with an aperture 27 through which a long negative electrode mayprotrude, as shown, the aperturebeing of suiiicient size to permitlimited swinging of the reflector with respect to the electrode. Thenegative electrode can be replaced through a erture 27 and an opening 28in the rear o the searchlight drum. The aperture 27, in Aaddition topermitting the use of a relatively long negative electrode, performsanother valuable function, in that the molten particles which fall fromthe electrodes can drop through said aperture without damaging thereflector.

In Figs. 2 and 3 is shown a modified form of my invention, wherein'theelectrodes are movable with the condenser or reflector 29. The latter ismountedon a suitable support 61 carried by arms 30 which projectupwardly from ring 31 and are pivoted to said ring by trunnions 32. Thering 31 is pivotally supported in standards 62 on base 46 for movementabout an axis 33, at right angles to the axis of trunnions 32. The lampmechanism which is carried by the support 61 may comprise 1lpper andlower housin s 34, 35, the lower housing being secured wit in acylindrical sleeve 63 which passes through a central opening in saidreflector and is secured to or formed integral with the support 61. Theupper housmg 34 is supported from said lower housing by suitable bars orstandards 36. The positive and negative electrodes are carried by theupper and lower housings respectively. One of the standards 36 may beemployed as a bus bar to lead current to the positive electrode and thusreflect the arc. As the details of the lamp mechanism are not essentialand form no part of my invention they will not be herein described.

For moving the mirror 29 aboutrthe axis of trunnion 32 I may employ amotor 37 carried by a bracket 38 depending from sleeve 63. Projectingdownwardly from said bracket is an arm 39 carrying va roller 40 which isreceived within the trackway 41 of a curved bail 42 depending'from ring31. A crank 43, mounted to rotate on a bracket 44 carried by arm 39, isdriven by motor 37. Connected at one end eocentricall to said crank is alink 45, the other en of said link being connected to said bail. Fromthis construction it will be evident that as lon Vas motor 37 isenergized the mirror 29 wil be oscillated about the axis of thetrunnions '32, during which time roller 40 will travel back and forth intrackway 41. For oscillating ring 31 and mirror 29 about the axis 33 Ihave shown a motor 47 on base 46, which motor drives a crank 48. A link49 is connected at one end to bail 42 and is connected eccentrically atits other end to v crank 48.

invention wherein the beam may be caused to describe a cone by rotatingthe refiector about only one axis. The searchlight drum 50 in thisfigure is mounted similarly to drum 1 and carries high intensityarc lampmech- `anism of any conventional type including `or optical axis of thereflector intersects the axis of rotation of the refiector at the focalpoint. The crater of the positive electrode 51 is, of course, preferablypositioned at said focal point. The. reflector or condenser 53 may berotated continuously by means of a motor 55, supported from casing 50,which motor drives a worm wheel 56 secured to shaft 54.

`When the mirror is in its full line position the searchlight beamoccupies the position shown in dot and dash lines while, when the mirroris turned through 180 into the position shown in dotted lines, the beamassumes its dotted line position. It will now readily be seen thattherotation of said mirror will cause the beam to describe a cone theaxis of which is the axis of-the searchlight. lit ywill be seen alsothat the effect of rotating the eccentricall mounted mirror 53 is tocause rotation o the beam about two axes at right angles to the axis ofrotation of said mirror.

A further modified form of my invention is shown in Figs. 5 and 6. Inthis modiiication the reiector is rotated about axes at right angles toeach other by two motors Aneither of which is movable about either ofsaid axes. vWhile it will be apparent that this form of invention may beapplied to rotating the refiector of Fig. 1 I have shown it inconnection with the construction of Fig. 2, wherein the refiector andlamp mechanism are movable together.` The ring 3l of Figs. 5 and 6 ispivotally supported by standards62 for movement about an axis 33', andthe refiector 29 is carried by a supporting member 61 which in turn issupported by arms 80 projecting upwardly. from ring 31 and pivoted tosaid ring by trunnions 32. The lamp mechanism is supported by thecylindrical sleeve 63 of member 61. The means for moving ring 3l aboutaxis 33 is shown as comprising a motor 66 which, through the medium of acrank 68 and link 69 causes oscillation of an arm 67 depending from saidring. For moving the reflector 29 about the axis of trunnions 32 I haveshown a bail 70 pivotally supported by standards 71 for movement aboutan axis coinciding with the axis of trunnions 32. Said ball is providedwith a trackway 72 in which is received a roller 73 carried bv an army74, which arm is shown as depending from the sleeve portion 63 ofmember 61. With this construction it will readily be seen that movementof bail about its axis of oscillation will, through arm 74, cause acorresponding movement of mirror 29 about the axis of trnnnions 32. Atthe same time, movement of said refiector with ring 31 aboutaxis 33 ispermitted by roller 73 and trackway 72. The bail 70 may be oscillated bya mo tor 75 which drives a crank 76, to which crank is connected a link77 in turn coneclted with an arm 78 depending from said a1 and 75 may bemounted on the base member 79 which supports standards 62 and 71, andthat the necessity of supporting either of It will be seen that bothmotors 66` said motorsfor movement with ring 31 or y reflector 29 isavoided. y

lt should be noted that in Fig. 1 the searchlight drum may be tiltedvabout a horizontal axis on base 2 and that the beam of light maythereupon be' caused to describe a cone by rotating the searchlightabout a vertical axis by meansof motor 64 and Wormwheel 65. This may bedone either simultaneously with or independently of the rotation ofreflector 12 with respect to the light source.

As in Fig. 1, the beam of Figs.`2 and 5 may be caused to move withdifferent periods about its horizontal axes of rotation and to traversedifferent paths by appropriately varying the vspeeds of the motors thatcause said beam to turn about said axes. Thus by running said motors atdifferent relative speeds the beam maybe given one period of rotationabout one axis and a different period about the other axis. Any

of a Wide variety of conventional means for varying the speeds of themotors may be utilized, and since such means are well known inthe art noshowing thereof in this application is thought to be necessary.Different paths of the beam may also be obtained, even though bothmotors run at the same speed by first commencing the rotation of thebeam about one axis and then, at any desired subsequent time during therotation .of said beam about said axis, commencing from another and todetermine his location or obtain other infomation.

As shown in Fig. 7, the glass front of the searchlight casin of Fig. 1may be omitted and the searchlig t may be exposed directly to theweather. In this case the hole 27 in the reflector 12 serves theadditional function of permitting the escape of any moisture which maycollect on said reflector. The hole 28 inthe bottom of the casing 1serves similarly to permit moisture to escape from said casing. Ifdesired, the rear wall or bottom 28 of the casing may be slightlyinclined on all sides toward the aperture 28 to facilitate the escape ofmoisture from the casing.

Fig. 8 shows still another modified form of my invention. In this-modication the mirror is mounted in a suitable supporting frame 81which in turn is secured a ring 82. The latter is pivoted by truiinions83 to an outer ring 84, which latter ring is pivoted to a suitablesupport 85 for movement about an axis 85 at right angles to the axis oftrunnions 83. The lamp mechanism may be supported by arms 86 extendingfrom ring 82. As shown, said lain mechanism may be similar to that shown1n Fig. 2 and comprises housings 87 and 88 which carry the positive andnegative electrodes respectively, and are in turn supported by the arms86. An aperture 89 in the bottom of reflector 8O and frame 81 may beprovided if desired, for permitting a long negative carbon to beinserted into housing 88. Said negative carbon is shown at 100 extendingthrough the bottom of housing 88 andY also through opening 89. Forrotating the reflector a motor 90 drives a crank arm 91 throu h themedium of suitable gears 92, 93. aid crank arm is shown mountedadjustably in a housing 94 rotatable with the shaft 95 of gear 93, theaxis of rotation of the latter preferably passing through the center ofthe gimbal mounting; i.' e. through the intersection of the axes ofrotation of the reflector. An aim 96 projecting from a spider 97 securedto the bottom of frame 81 is connected through a universal joint 98 withsaid crank 91. The arm 96 may be slidable in the ball of the universaljoint.- It will be seen that by the -construction above described, thereflector can be rotated by motor 90 about the pivotal axes of bothrings 83 and 84 continuously and simultaneously and that by adjustingcrank arm 91 in housingv94 the throw imparted to the reflector may .bevaried as desired. A set screw or bolt 99 may be provided for lockingsaid crank arm in adjusted position in said housing.

In accordance with the provisions of the patent statutes, I have hereindescribed the principle of operation of my invention, to-

gether with the apparatus, which I now consider to represent the bestembodiments thereof, but I desire to have it understood that theapparatus shown is only illustrative and that the invention can becarried out by other means. Also while it is designed to use the variousfeatures and elements in the combination and relations described, someof these'may bealtered and others omitted without interfering with themore general results outlined, and the invention extends to such use.

Havin described my invention, what I claim an desire to secure byLetters Patent is: v

1. In combination, a reflector mounted for movement about axes at anangle to each other and to the vertical, a crank arm, means for rotatingsaid crank arm about a vertical axis, and a connection between' saidreflector and said crank arm for causing rotation of the reflectorsimultaneously about said first mentioned axes.-

2. An aviation beacon comprising in combination an arc searchlightarranged to normally project a beam of parallel rays vertically, meanssupporting said searchlight about a plurality of axes, and means 1ocatedbelow said searchlight for continuously moving it about sa1d axessimultaneously vcomprising a motor, and a crank irn driven therebyconnected to the searchig t.

3. An aviation beacon comprising in combination a ring, a reflector, anarc lamp supported thereon arranged to normally project a beamvertically, a second ring pivotally supporting said ring, means ivotallysupporting said second ring at right angles to the pivotal axis of saidfirst ring, and means for continuously moving said rings about theiraxes simultaneously including a motor and a crank arm whereby theprojected beam is caused to travel in the path of a cone.

4. An aviation beacon, comprising in combination an arc searchlight, aCardan suspension for said searchlight, and means for continuouslyoscillating said searchlight about a plurality of axes of saidsuspension, said means including a source of power and a crank armconnecting said source of power to said searchlight.

5. An aviation beacon, comprising in combination an arc searchlight, aCardan suspension for said searchliglit, means for continuouslyoscillating said searchlight about a plurality of axes of said susension, and means whereby said last-name means may be adjusted to varythe path of the reflected beams.

Intestimony whereof I have affixed my signature;

" ELMER A. SPERRY.

